Viggo Mortensen posed with Kristen Stewart (left), wearing Balenciaga, and Kirsten Dunst, who wore a fuchsia Christian Dior gown, at the screening of ‘On the Road.’

The stars continue to showcase their expansive designer wardrobes at the 65th annual Cannes Film Festival, now a full week into the event.

Kristen Stewart, as a brand ambassador for Balenciaga, wore the label twice in one day to promote “On the Road.” Co-star Kirsten Dunst opted for two lady-like looks with a white Dolce & Gabbana dress and a fuchsia Christian Dior gown.

Meanwhile, couple-of-the-moment Kanye West and Kim Kardashian stepped out together for a screening of “Cruel Summer.”

Tom Brady showed up with a jarring hairdo, Brooke Shields hobbled up stairs and down the red carpet with a cane and Anna Wintour had a lobster spilled all over her white gown.

Those were just a few of many curious moments at Monday night’s big Metropolitan Museum of Art’s Costume Institute gala benefit, also known as the Met Ball, The Party of the Year, and more recently, the Oscars of the East Coast.

Held every first Monday of May, it’s a star-studded affair. To secure a coveted invite means you are on the A-list or on the up and up (Jessica Paré, who plays Megan Draper on “Mad Men,” for example). Gawking at what celebrities are wearing and whether a starlet will make it up all those stairs in a flowing gown with grace or difficulty has become a spectator sport since Ms. Wintour took over as a co-chairwoman of the gala in1995. She brought sizzle and star power to the event by inviting some of the biggest names from Hollywood, sports and music to the event, along with fashionistas from around the world.

Alec Baldwin with fiancée, Hilaria Thomas, at the New York Ermenegildo Zegna store Wednesday night

Alec Baldwin did more than pose for pictures, take journalists’ questions and shake hands with assorted guests and well-wishers while at Ermenegildo Zegna’s New York flagship store Wednesday evening for an event celebrating its new pure silk collection. He also took time to buy a tie.

Michelle Obama wore a Naeem Khan dress with a vibrant print to the annual White House Correspondents’ Association dinner at the White House on Saturday. Meanwhile, Lindsay Lohan chatted with Rick Santorum, and George Clooney caught up with former U.S. Secretary of State Colin Powell. View the slideshow after the jump.

The season has barely sprung, but Paula Abdul is getting started on spring cleaning.

The former American Idol judge is selling some 1,500 items from her personal wardrobe through Linda’s Stuff Inc., an online consignment company that sells goods on eBay and other sites. Weeklong auctions of Ms. Abdul’s shoes, apparel and accessories begin today.

The sale is Ms. Abdul’s second round of closet-clearing via Linda’s Stuff, which hosted a sale for her this past December. Some of the proceeds from the sale will be donated to PAWS and the Make-A-Wish Foundation.

It was fashion to die for at the Hunger Games premiere Monday. All eyes were on Jennifer Lawrence, who stars as Katniss Everdeen in this fight-to-the-death trilogy. Lawrence stole the show in a gold Prabal Gurung fall 2012 gown. The dress, first seen last month during New York fashion week, was as fierce as her character with triangle cutouts at the rib cage and an open T-shaped back. See more looks after the jump.

At Yves Saint Laurent tonight, Balenciaga designer Nicholas Ghesquiere was seated right in front of me. Salma Hayek came over to whisper conspiratorially in his ear — something about someone getting married. Her husband, Francois-Henri Pinault, slapped Ghesquiere on the back. He’s CEO of PPR, which owns both YSL and Balenciaga. They seemed a happy clique. But to the right was Alicia Keys. Catherine Deneuve was seated across the runway, right next to Mr. Pinault’s seat. Somewhere else in the room, according to the Twittersphere, Katy Perry was turning heads.

All this was a tribute to a designer — Stefano Pilati — who was showing his last collection for the label.

About Heard on the Runway

Heard on the Runway provides news about the fashion and retail worlds, as well as fresh analysis and dispatches from the bi-annual fashion shows in New York, Milan and Paris. For complete style coverage, go to WSJ.com/Fashion.